One of the problems associated with increasing performance in multiprocessor parallel processing systems is the efficient accessing of data or instructions from memory. Having adequate memory bandwidth for sharing of data between processors is another problem associated with parallel processing systems. These problems are related to the organization of the processors and memory modules and the processor architecture used for data communication between a processor, including execution units, and a plurality of memories and between processors. Various approaches to solving these problems have been attempted in the past, for example, array processors and shared memory processors.
Multiprocessor systems can be classified generally in terms of coupling strength for communication between processors. Those multiprocessor systems that communicate using a share memory facility between the processors and the shared memory over an interconnection network are generally considered tightly coupled. Loosely coupled multiprocessor systems generally use an input/output (I/O) communication process in each processor for communicating between the processors over an interconnection network, such as message passing process. A wide variety of interconnection networks have been utilized in multiprocessing systems. For example, rings, bus connected, crossbar, tree, shuffle, omega, and butterfly, mesh, hypercube, and ManArray networks, have been used in prior multiprocessor systems. From an application or use perspective, specific networks have been chosen primarily based upon performance characteristics and cost to implement tradeoffs.
Parallel processing and the distribution of data between functional execution elements may be described using Kronecker product expressions of signal transform functions, such as the fast Fourier transform (FFT) and other signal flow graph expressions. However, the underlying processor architecture may present limitations that affect the efficiency of implementing functions described using Kronecker product expressions and other signal analysis techniques.